title: Visit-to-visit systolic blood pressure variability and outcomes in hemodialysis.
abstract: Visit-to-visit blood pressure variability (VTV-BPV) is an independent risk factor for cardiovascular events and death in the general population. We sought to determine the association of VTV-BPV with outcomes in patients on hemodialysis, using data from a National Institutes of Health-sponsored randomized trial (the HEMO study). We used the coefficient of variation (CV) and the average real variability in systolic blood pressure (SBP) as metrics of VTV-BPV. In all, 1844 out of 1846 randomized subjects had at least three visits with SBP measurements and were included in the analysis. Median follow-up was 2.5 years (interquartile range 1.3-4.3 years), during which time there were 869 deaths from any cause and 408 (adjudicated) cardiovascular deaths. The mean pre-dialysis SBP CV was 9.9 ± 4.6%. In unadjusted models, we found a 31% higher risk of death from any cause per 10% increase in VTV-BPV. This association was attenuated after multivariable adjustment but remained statistically significant. Similarly, we found a 28% higher risk of cardiovascular death per 10% increase in VTV-BPV, which was attenuated and no longer statistically significant in fully adjusted models. The associations among VTV-BPV, death and cardiovascular death were modified by baseline SBP. In a diverse, well-dialyzed cohort of patients on maintenance hemodialysis, VTV-BPV, assessed using metrics of variability in pre-dialysis SBP, was associated with a higher risk of all-cause mortality and a trend toward higher risk of cardiovascular mortality, particularly in patients with a lower baseline SBP.
authors.affiliation: Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Palo Alto, CA, USA.
authors.forename: T I
authors.initials: TI
authors.lastname: Chang
authors.forename: J E
authors.initials: JE
authors.lastname: Flythe
authors.forename: S M
authors.initials: SM
authors.lastname: Brunelli
authors.forename: P
authors.initials: P
authors.lastname: Muntner
authors.forename: T
authors.initials: T
authors.lastname: Greene
authors.forename: A K
authors.initials: AK
authors.lastname: Cheung
authors.forename: G M
authors.initials: GM
authors.lastname: Chertow
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination; D002318:Cardiovascular Diseases / Q000401:mortality* / Q000503:physiopathology; D002423:Cause of Death; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D012307:Risk Factors; D013599:Systole